ELECTROCUTION IS A LEADING CAUSE OF DEATH AMONG CONSTRUCTION WORKER FATALITIES, ACCOUNTING FOR 8.5% OF TOTAL FATALITIES IN 2018.
The primary cause of death over 50% of these fatalities was contact with live electrical equipment and wiring. Even though overhead electrical work has long held consistent standards, safety protocols for ground crews on de-energized sites are often more ad-hoc and improvisational, which means increased risk for workers.
Ground crews may suffer injury or even death from step and touch potential. Step potential is when an individual steps on a surface with high voltage and the current carries from one foot through the rest of their body. Touch potential is when the current carries through an individual’s body as a result of a direct touch. It takes 50 volts to break the electrical resistance of skin and cause injury. Serious injuries, or even death, may occur from exposure levels of no more than 50 milliamps.
The IEEE recommends the accepted practice of developing an equipotential zone (EPZ)1, which bonds together all accessible conductors, structures, components and equipment through at least one low-resistance paths. This bonding practice limits voltage exposure to the workers on a de-energized construction site. Grounding protection works to discharge voltage from nearby energized objects, reducing voltage to below a level that might cause injury to a worker.
While grounding causes the immediate operation of a circuit protective device to protect the equipment, a grounded circuit still has an active current which can contain voltage. To protect personnel on the ground from this voltage potential, it is essential to implement bonding.
Many contractors believe that dropping chain-link fencing, wiring or other makeshift solutions are good enough when it comes to protecting their employees. What they fail to consider, however, is the risks that these thrown-together systems present. Because they are not made to be walked on or rolled over with machinery, they can deform or break apart under stress. This creates trip-and-fall hazards in addition to dangerous gaps in what little protection they provide against high voltage.
Using timber or composite mats is another common strategy that does more harm than good. That’s because these can bend, crack and decompose over time. They won’t protect your workforce from electrical discharges, touch-and-step potential or other hazards the same way a quality EPZ grounding system could.
The EPZ Grounding Grate is a one-piece galvanized steel grate used to create an equipotential bonded and grounded work zone. This zone then protects crews from step-potential and Grade 5 fault currents. EPZ Grounding Grates are positioned on the ground then bonded together with 4/o copper cables and 2-hole lug connectors, creating an equipotential zone for puller/tensioner sites, and portable substations. The additional lug areas on EPZ Grounding Grates are for securing grounding cables between stringing equipment and grates. Our grates are quick to install and bolt together, allowing for quick assembly and easy removal.
While it’s possible to create makeshift EPZ systems, it’s not a good idea to do so for the safety and business reasons outlined above.
Instead, when choosing an EPZ grounding system to protect your ground workers, consider these factors:
Made from all-in-one galvanized steel grates, SAFESTEPTM EPZ grounding grates offer superior protection in these high-voltage situations. They’re built to withstand heavy loads and extensive use. Combined with how easy they are to install and dismantle, these can be a viable solution for your jobsite needs.